Science And Human Sexuality

When we talk about the morality of different kinds of sexual interests, the question of ‘what science tells us’ often comes into the conversation. The point usually being made is that we now know much more about human sexuality than in biblical times so we need to revise or update our thinking about the moral issues as well.

The question of how science relates to our understanding of human sexuality in fact has a long and controversial history. On one side of the debate, people have sometimes used labels of illness to pathologise and humiliate people considered to be different from them. Until 1973, for example, homosexuality was considered by psychiatrists to be an illness in need of a cure. On the other side, revisionist theologians have sometimes deployed science (without really understanding it) to imply that the Bible no longer has anything relevant to say on this issue. So we need to think carefully about how science works, and what it can actually contribute to serious theological debate and moral reasoning in this area. And we need to be especially vigilant to the way that science is used (on all sides) for political leverage and point scoring.

It is not possible here to review the vast number of (often contradictory) scientific claims about the complex area of human sexual interests. But we do need to consider the more fundamental questions that lie behind them.

The latest scientific discoveries often turn out to be wrongScience is the pursuit of knowledge and understanding of the natural and social world based on painstaking observational evidence and repeated experimentation. The conclusions of scientific thinking are most reliable when they have been tested repeatedly under experimental (controlled) conditions. But in many areas it is difficult to carry out repeat tests under laboratory-type conditions. The vagaries of the ‘science’ of economics is a case in point. And in complex areas such as the study of human behaviour, individual observations have to be merged to create bigger theories, or stories, to try to explain what is going on, and these are extremely difficult to test experimentally under controlled conditions. That is why we get newspaper headlines of ‘study proves X’ one day, and then ‘study disproves X’ the next, each backed up with pie charts and professorial talking heads.

Science methodology has delivered enormous social and material goods for human civilisation. But when we hear about the latest science claims in the sphere of sexuality, we should retain a healthy scepticism: there is no substitute for checking the facts carefully for ourselves and asking: Are these claims really justified by the evidence? The popular notion that there is a ‘gay gene’ is a good example of how small unproven studies may be seized on, popularised and then used by media elites to shape a whole new cultural understanding of the way things work. But as we see in another article, the evidence for a ‘gay gene’ turned out to be very weak indeed.

Science and morality function in different categories Even when a scientific discovery seems reasonably reliable, we need to be careful about using it to support a particular line of moral reasoning. Science can help us to map and investigate our experiences, but it can’t interpret them or answer questions about moral value. Science can help us to understand factors that predispose us to experiencing certain attractions, and it can make predictions about the outcomes of different courses of action, but it can’t tell us what we should actually do about our wants and desires. These are different categories of analysis and we shouldn’t confuse them.

Take the case of promiscuity. Certain genetic profiles may turn out to be linked with a tendency toward seeking ‘one-night stands’, especially those genes, or groups of genes, that are associated with personality traits such as impulsiveness and novelty-seeking. But that doesn’t absolve us from the need to test our desires against moral standards and beliefs and to control our behaviour in line with them. So when we hear the latest claims about science and ‘what we now know’, we should handle with care: science can’t settle the moral status of different human sexual interests.